If you think about your age every day, you are the stupid one around here. Or maybe you are just 13 and it's easy because you eagerly await the next year so you can be treated a little bit more like an adult so you count the days.
My exact age is almost never relevant in my day-to-day life, I pretty much only get reminded of it on my actual birthday and don’t think much about it for the rest of the year. So if somebody asks for my age, usually I’ll be off by a year or two and my wife will need to correct me, because for some reason she remembers.